Different Trajectories of Parallel Evolution During Viral Adaptation
H. A. Wichman,
1*
M. R. Badgett,
2
L. A. Scott,
1
C. M. Boulianne,
1
J. J. Bull
23
The molecular basis of adaptation is a major focus of evolutionary
biology, yet the dynamic process of adaptation has been explored only
piecemeal. Experimental evolution of two bacteriophage lines under
strong selection led to over a dozen nucleotide changes genomewide in
each replicate. At least 96 percent of the amino acid substitutions
appeared to be adaptive, and half the changes in one line also occurred
in the other. However, the order of these changes differed between
replicates, and parallel substitutions did not reflect the changes with
the largest beneficial effects or indicate a common trajectory of
adaptation.
1 Department of Biological Sciences, University
of Idaho, Moscow, ID 83844, USA.
2 Department of
Zoology and
3 Institute of Cellular and Molecular
Biology, University of Texas, Austin, TX 78712, USA.
*
To whom correspondence should be addressed. E-mail:
hwichman{at}uidaho.edu
